Physiological specimens of fluids such as blood are collected in closed receptacles from which samples must later be removed for testing. One well-known type of container exemplifies the problem solved by this instant invention. This is the "Vacutainer", which is a glass vial closed by a stopper-like septum. It is sold evacuated so that when it is opened to a needle inserted into a vein or artery the vacuum inside the container draws blood into the container.
This closed container with its contents is centrifuged to settle the red cells and separate the plasma or serum as a supernatant liquid atop the red cells. The problem is how safely to extract some of the fluid for further use, when the fluid may contain material which is dangerous to the technician.
For many years, the removal of fluid from a specimen container was considered to be no more complicated than the removal of the stopper and the transfer of the fluid with a pipette. However, with the increasing dangers of some diseases carried in the blood such as AIDS and hepatitis, health workers who must work with blood. their employers, and society in general, have been justifiably concerned about physical contact with the blood samples. A preponderance of specimens are taken from persons who have or may have serious ailments. The operator does not know what risks may be in the sample. Often enough neither does the patient or the physician who ordered the test. Accordingly, every sample must be treated as though it is the worst possible example.
As a consequence there exists a conflict between necessary speed in order to keep tests affordable, and risks inherent in rapid handling. What is needed is a means quickly and safely to remove a sample from a container without exposing the operator to risks of contact with the fluid, or with a spray of the fluid.
Also, it is axiomatic that one sample must not be permitted to contaminate other samples. In some systems the same needle is used from sample to sample, requiring a cleansing and sterilizing step between each use of the needle. This requires additional expense by way of extra equipment or of added time, both of which increase the cost of the test.
Of course these objections have long been recognized, and efforts have been made to overcome them. Still there remain serious disadvantages and risks. Some of these would have been of little concern before the appearance of AIDS, but now they are. One example is the tendency of a spray, however slight, that can be generated when the septum is removed to give access to the contents of the container. This is not an insignificant risk, especially in a laboratory where many of these are removed per hour.
There are obvious means by which one can seek to alleviate this situation. Performing the manipulations in a hood or other negative air flow region is one of them Again, the cost of the installation and of the manipulations increases. Also there is the costs of simply removing the cap to carry out the procedure.
It is an object of this invention to provide a septum piercer and extractor which can obtain uncontaminated samples from containers affordably and without cross-contamination, and without any exposure of the operator to the specimen or sample.